feat: REV-4051 | allow edx_django_service to be provided with specific app names to run datadog on

fix: interpolation for DD installation conditional. also formatting

fix: Apply suggestions from code review

Co-authored-by: Tim McCormack <[email protected]>

fix: update variable name

fix: update j2 file with new conditional

Author: christopappas

playbooks/roles/common_vars/defaults/main.yml

@@ -102,6 +102,7 @@ COMMON_MONGO_READ_ONLY_PASS: !!null
 COMMON_ENABLE_DATADOG: False
 # Enable APM monitoring with Datadog (metrics, traces, and logs)
 COMMON_ENABLE_DATADOG_APP: False
+COMMON_ENABLE_DATADOG_APP_SERVICES: []
 COMMON_ENABLE_NGINXTRA: False
 COMMON_ENABLE_SPLUNKFORWARDER: False
 COMMON_ENABLE_NEWRELIC: False

playbooks/roles/edx_django_service/defaults/main.yml

@@ -104,6 +104,7 @@ edx_django_service_basic_auth_exempted_paths: '{{ edx_django_service_basic_auth_
 edx_django_service_newrelic_appname: '{{ COMMON_ENVIRONMENT }}-{{ COMMON_DEPLOYMENT }}-{{ edx_django_service_name }}'
 edx_django_service_enable_newrelic_distributed_tracing: false
 edx_django_datadog_service: 'edx-{{ edx_django_service_name }}'
+edx_django_service_datadog_enable: '{{ COMMON_ENABLE_DATADOG and (COMMON_ENABLE_DATADOG_APP or edx_django_service_name in COMMON_ENABLE_DATADOG_APP_SERVICES }}'
 
 edx_django_service_repos:
   - PROTOCOL: '{{ edx_django_service_git_protocol }}'

playbooks/roles/edx_django_service/tasks/main.yml

@@ -213,7 +213,9 @@
     - install:app-requirements
 
 - name: "Install Datadog APM requirements"
-  when: COMMON_ENABLE_DATADOG and COMMON_ENABLE_DATADOG_APP
+  when: >
+    COMMON_ENABLE_DATADOG and
+    (COMMON_ENABLE_DATADOG_APP or edx_django_service_datadog_enable)
   pip:
     name:
       - ddtrace

playbooks/roles/edx_django_service/templates/edx/app/app/app.sh.j2

@@ -20,7 +20,7 @@ fi
 export NEW_RELIC_LICENSE_KEY="{{ NEWRELIC_LICENSE_KEY }}"
 {% endif -%}
 
-{% if COMMON_ENABLE_DATADOG and COMMON_ENABLE_DATADOG_APP %}
+{% if COMMON_ENABLE_DATADOG and (COMMON_ENABLE_DATADOG_APP or edx_django_service_datadog_enable) %}
 {% set executable = edx_django_service_venv_bin + '/ddtrace-run ' + executable %}
 export DD_TAGS="service:{{ edx_django_datadog_service }}"
 export DD_DJANGO_USE_HANDLER_RESOURCE_FORMAT=true